1. Field of the Invention:
The present invention relates to an apparatus for manufacturing a continuous slide fastener stringer including a stringer tape and a row of injection-molded coupling elements secured to the stringer tape along a longitudinal edge thereof.
2. Prior Art:
One example of such apparatus as described is disclosed in the Japanese Patent Publication (Kokoku) No. 53-28309 published on Aug. 14, 1978. The disclosed apparatus includes a pair of fixed and movable mold members having a predetermined number of cavities, and a tape feeder disposed downstream of the movable mold member for intermittently advancing successive parts of a stringer tape one at a time, one of successive parts of the tape extending through the mold members at an angle to confronting mold surfaces of the latter. The stringer tape's part thus held is liable to be displaced out of alignment with the mold cavities as the movable mold member is moved to its fully closed position. A beaded, element-supporting edge of such misaligned tape's part is partly deformed or otherwise crushed by the mold surfaces, and a row of injection-molded coupling elements secured to such crushed element-supporting edge cannot perform a requisite function.
Another apparatus disclosed in Japanese Utility Model Laid-open Publication (Kokai) No. 55-10733 published on Jan. 23, 1980 comprises a feeler projecting from a mold surface on a fixed mold member toward a mating mold surface on a movable mold member and engageable with the trailing end of a group of injection-molded coupling elements secured to a portion of a stringer tape to position a succeeding part of the stringer tape with respect to the mold members. The disclosed apparatus, however, has no means for moving the stringer tape between a position in which the tape is spaced from the mold surface and held out of interference with the feeler, and a second position in which the tape lies flatwise on the mold surface. With this arrangement, the movement of the movable mold member toward the fixed mold member must be temporariry interrupted for a period during which time the stringer tape is fed in the a reverse direction until the trailing end of the previous injection-molded coupling elements abuts against the feeler. The apparatus thus constructed is difficult to operate at a relatively high speed.